We are two college students who have been lurking on this community for some time as we made preparation to get ourselves an octopus. We followed all the suggestions and have set up a good quality 90 gallon. A month and a half ago we purchased the octo from saltwaterfish, and have since hit an issue.

Our octo has not left its den (to our knowledge) in the entire time that we've had it. We realized a while back that this was due to our blue LED lighting, which must've been too bright for it, and so switched to red LED. All other conditions are optimal. However, it still refuses to come out at all. The live fiddlers we offer have stopped disappearing, so we began feeding it ourselves by offering shrimp on a bamboo skewer every day. It reaches out, three tentacles max at a time, probes at it, but doesnt seem to take any. It does this several times until it eventually stops pulling at it and instead swats it away.

We are concerned about this behavior and are looking for ways to coax it out and get it eating more. Please let us know your suggestions and if you've ever had experience with an octopus this shy/scared for this long. How should we proceed? We will be updating this journal as we go, but of course we have no photos yet, as all we've seen since putting it in is a few tentacles sticking out of a rock, hence its name.

How long did the tank and live rock cycle?
Have you checked the water/salt/ammonia/nitrates levels?
Water temp?
Any photos of your set up and tank?
Any photos of your ceph?

If you made it past your first couple of weeks... for the first month or 3, if it is young, you're lucky to see the ceph much.

Have you tried a teeny piece of shrimp on a long stick where it (name?) hides?
Don't tug of war, resist the urge.
Teeny, like, peace sized, a small pea.

You can ways try another piece, let it refuse.

Maybe the fiddlers are too big yet. You can try hermits, small ones. Sometimes octos will eat them OR at least attack or hug them and lug them around.

Little things in the tank, like shells, can entice your ceph to build a door. It's a good tricky to figure out if your ceph is out and about.

Try to keep positive. If you've been reading along in the threads, sometimes you end up with a traumatized ceph, or a sick ceph, or a super hidey ceph. Feed it, love it, get it little things to build or play with, and it might come out after a while.

Octopus pets often try our patience. One way or another.

Ps you don't have fish in the tank... Correct? Take them out if you do.
I learned my lesson withat that.

No fish in the tank, all water conditions optimal and confirmed regularly by test kit, and we had a cycling period of more than two months. The only thing is that temp has been rather high lately due to these intense two weeks. We've managed to cool the water down by putting in large RO/DI ice cubes every day.

Our octopus (Rocktopus; named so because from our perspective, it is merely a rock that occasionally waves tentacles) had built a door earlier, apparently using a piece of rock it broke off. It has since removed the door and doesn't use one any more, but had the materials to make one if it needs. We have tried hermits from very small to fiddler size. Whenever they crawl near its den, it grabs them and flings them away.
We have been feeding it shrimp exactly as you describe. The other night it managed to break off a tiny piece, swung it around a bit, and then simply dropped it on the ground.

We'd love to hear suggestions on encouraging it to come out. Our primary concern is making sure it is eating well and staying healthy, but never getting to see it and struggling to feed it every night is a poor return on investment.

Rocktopus plays with the shrimp for a bit, pulls it toward the den and we offer no resistance. It will do this for 40 minutes to an hour, not visibly taking any pieces, and then begin pushing it away at some point.

Maybe have the shrimp piece be very loose on the stick. Maybe it doesn't get food must be pulled off. Maybe.

Try fresh clam.

Enjoy the look the seafood counter guy gives you when you ask for just one, lol.

Let the clam sit in cool water, rinse the muck off, let it filter a little, and stick your knife in it to open the shell for the octopus. I scrape it and cut into it a bit to make it easier to grab and take.
Can also try pieces of it on a stick.

@Jocco has covered most of the suggestions I might offer except the possibility that you have a brooding female (either with eggs in your aquarium or having laid eggs before she was caught, a senescent male is more likely to be very active while not eating). It may be eating small crustaceans in the tank (amphipods) but it is not normal for an animal that WAS eating small crabs (fiddlers) to stop unless it is brooding and/or in senescence. Since it is not maintaining a door, there may not be eggs but the symptoms are common to brooding and a female will continue to brood if removed from her eggs.

Do you remember anything about the size or other features when it arrived (best guess is best you can do for this one but in the future, I highly recommend photographing during acclimation). Size, however, is not much help after a point as they all vary significantly. A female with ripe eggs can sometimes be spotted from the distended and somewhat floppy mantle. However, I find this easier to note when I have observed the animal for a month or more.

Our primary concern is making sure it is eating well and staying healthy, but never getting to see it and struggling to feed it every night is a poor return on investment.

Click to expand...

LOL, There is NO good ROI in this hobby (saltwater aquariums in general but this is true of most hobbies). Octopuses, in particular, are short lived (8-18 months for the species kept at home and you don't know the age when they arrive). I always advise setting up a tank that can accommodate any of the most common species (which you seem to have done) because of the short lifespan. That being said, I hope you are not too discouraged with your first animal.

Sad, but part of the cycle of their life, and keeping these wonderful creatures.

I do hope they try again! Although an investment, it's priceless when you get an active, quirky octopus lol!

I'm also wondering how long they've had the ceph, see if it's from the same area mine came from. If there is a species popular this time of year etc. Help them ID, help me ID. Further the amazing amount of info in this forum.

Based on stories heard and what we've read from the board, I'd say it's easily worth the trouble to keep an octopus and we'd try again if necessary. It's just that we spend so much time stressing about this one..

I'll recount my experience from the acclimation about what we saw of it.
It was about 2-3 inches, and spent most of its time curled into as tight a ball as possible in the corner of its bag. It was maintaining a uniform light gray color and had a lighter, almost white underside. The mantle was short and we did not notice it to be distended or floppy.

Before transferring, we introduced a small fiddler into its acclimation bucket to make sure it ate before going into the tank. It stayed curled up, but used a single tentacle to push the crab away if it got too close. We never could get it out of the bag and had to transfer it to tank with that scrap of plastic. For this reason, we never got photos of it spread out or moving. Below is the only shot I have from then where you can somewhat make it out.

Rocktopus has just been spotted outside of her den breathing VERY heavily and not moving her tentacles. The mantle seemed indented almost. She didn't make any attempts to remain right-side-up and to my untrained eye seemed to be displaying symptoms of senescence . We have separated her from the hermits in the tank. No eggs visible in the den, but its too deep and twisty to really tell.

Should we do anything else for her at this point?
If this is the end for her, we are determined to try again. What should we check about the tank to make sure it's hospitable to a new octo and there's no risk this might happen again?

The older the tank, the better I have noticed. Lots of proper tank mates and clean team (potential food).
I learned if I can keep shrimp alive, it's a good indication of the levels in the tank. Too soon, will just kill things. It's painful to wait for a tank to mature.
Buy fake plants or places to hide or hermits to help fill the void. Hermits are funny to watch.

Resist getting a star, especially sand sifters, they die. Pistol shrimp are fun. They eventually get eaten, but they dig, make homes, move sand, and click until they get eaten.
Pencil urchin and brittle stars are cool too. Try to get cleaner shrimp in pairs, but not too many, they can pick on your ceph.

Giving it places to hide helps. Maybe give it glass shrimp or much more food to hunt.

If you have a kritter keeper or breeder net, you can put Rocktopus in there.

She may have already laid her eggs before being introduced to your tank. Since it lived this long, acclimation does not seem to be the problem but be sure to allow 3 hours of slow water exchange when acquiring one that has been shipped or the LFS water is different from the water in your aquarium. The PH of shipped animals is almost always significantly different.

I suspect you received a senescent animal but when you mention tank parameters, please give the actual numbers for salinity and PH as there is a recommended difference for salinity (lower for fish than for corals and inverts). Also confirm 0 nitrites and ammonia. Either of these not being zero can cause senescent like symptoms and death. Nitrates are less I important for an octopus (not so for many corals).

We did our last water change just more than a week ago, so I was expecting ordinary conditions, but I just performed another test and here are the specs:
Salinity has been maintained at SG of 1.026
pH was and is around 8.2
Ammonia is between 0 and 0.25 ppm, closer to 0
Nitrates have apparently risen recently and dramatically, to 10ppm.
Nitrites too have spiked to 1.0ppm

This is bad. Obviously we will need to perform a major water change before taking any other steps, but what could've caused such conditions to occur? How can we increase the level of our biofiltration?

The ammonia and nitrites are a definite concern (nitrates are fine). While you have an animal in residence, there is no good way to continue to cycle (increase your biofiltration) the tank so frequent water changes are the best way I know of to minimize the negative effects of decaying food and waste. When you lose this one, you can increase your cleanup crew and then over-feed them (I recommend ground grocery store shrimp in small quantities but meaty dry foods will also work). Hermit crabs, serpent or brittle stars (avoiding the green brittles) and pencil urchins will all eat the meaty scraps and can remain in the tank with an octopus (hemits may become supper). This method WILL raise your nitrates (and you still want to do regular water changes). Snails are always welcomed for algae but won't help with cycling.